Manufacture of die blocks and the like



Patented Oct. 10, 1933 UNITED STATES PATENT OFFICE MANUFACTURE OF DIE BLOCK S AND THE LIKE No Drawing. Application October 4, 1930 Serial No. 486,509

8 Claims. (Cl. 22-200) This invention relates to the manufacture of cast'steel die blocks and the like that are used for pressing or forging metals, such as steel, for example, into different forms or shapes.

Heretofore, in manufacturing die blocks and the like in which there is alarge body of metal with comparatively small openings, cavities, or depressions therein, blocks of steel have been forged or cast in molds, a surface thereof faced on a planer or milling machine to make the same smooth and metal removed to form the desired cavity in the block. This requires a long time and is an expensive operation. Also great care must be exercised in forming the desired cavity in the die block, as a few thousandths of an inch difference in size of the cavity renders the die block unsuitable for its intended use. Attempts have been made to obviate this difliculty by first casting a small insert having the desired cavity therein and then casting the heavy block about this insert. Troubles have arisen with this sort of die block because the insert is often not properly fused to the main body of the block.

Attempts have also been made to cast steel die blocks and the like by using sand molds of such shapes as to leave the desired cavities in the blocks. This procedure has not been found to be satisfactory because the sand of the mold that was shaped to form the cavity in the block burns in when the large mass of steel is poured around it, so that the proper cavity is not left in the block. In fact, the sand and steel combine in the cavity as an extraordinarily hard material that is practically impossible to remove in such a way as to leave the desired smooth cavity in the die block.

By the present invention steel die blocks can be cast in molds with smooth depressions or cavities of the exact size as desired even when the weight or" the die blocks exceeds several hundred pounds. In carrying out this invention. molds into which the steel die blocks are cast may be made oi materials which have higher iusien points than silica sand and give sharp eieamcut outlines and no "burning in" of the semi. Or, the molds or cores thereof may be with such a material instead of making the entire mold thereof.

n1 carrying out the invention we use moldrutile, magnesite, bauxite and other refractory materials of high fusing temperatures that can be made in the forms of grains or sand. The zircon sand has so far been found to be the most satisfactory material for this purpose, as it 00 has a very high specific gravity and high fusing point and occurs innature with smooth grains that can readily be formed into molds.

Bonding materials that are ordinarily used for silica sand molds may be used when desired in connection with the superrefractory sand out of which the molds are formed in accordance with our invention. The molds may not only be made up entirely of the superrefractory materials, but they may be made up of ordinary sand lined with the superrefractory materials, and also cores may be made up of the superrefractory material and inserted into molds made of ordinary sand, which cores can be removed after the steel has cooled, leaving the impressions or cavities that are true to size and have smooth walls. Impressions or cavities several inches deep can be made in the steel die blocks in this way by'using cores that may be made of the superrefractory material or may have the superrefractory material along the outer surfaces thereof.

We claim:

1. The process of forming cast steel die blocks and the like, which comprises forming a mold of zircon sand and pouring molten steel into said mold.

2. The process which comprises forming a mold having a hollow portion of the shape of a die block, forming a small core in said hollow portion having zircon sand composing the outer surfaces thereof having the shape of a die block cavity, and pouring steel into said mold.

3. The process of forming cast steel die blocks and the like, which comprises forming a mold having a hollow portion of the shape of a die block, forming a small core of zircon sand in said hollow portion having the shape of a die block cavity, and pouring molten steel into said mold.

' LE RUE P. BENEll'NG. I

KARL V. 

